diff --git a/apps/news/serializers.py b/apps/news/serializers.py
index 417db72e..6814965a 100644
--- a/apps/news/serializers.py
+++ b/apps/news/serializers.py
@@ -282,6 +282,7 @@ class NewsBackOfficeGallerySerializer(serializers.ModelSerializer):
         """Override validate method."""
         news_pk = self.get_request_kwargs().get('pk')
         image_id = self.get_request_kwargs().get('image_id')
+        is_main = attrs.get('is_main')
 
         news_qs = models.News.objects.filter(pk=news_pk)
         image_qs = Image.objects.filter(id=image_id)
@@ -297,6 +298,9 @@ class NewsBackOfficeGallerySerializer(serializers.ModelSerializer):
         if news.news_gallery.filter(image=image).exists():
             raise serializers.ValidationError({'detail': _('Image is already added')})
 
+        if is_main and news.news_gallery.main_images().exists():
+            raise serializers.ValidationError({'detail': _('Main image is already added')})
+
         attrs['news'] = news
         attrs['image'] = image